Are we talking Heidenhain? If so, try creating a program no. 0 to store tool data in. This option may depend on parameters - I didn't know about it myself until I switched jobs.
Defining tool data at start of program is not so bad if you are only working on one operation at a time. If you are running multiple ops, set-up a standard sub to define your tools.
Note that if they are using separate tool lists they are also probably using the dreaded 'zero' tool ....aaaaaaarrrrggghhhh!!!!!!!
ps if we are not talking Heidenhain disregard everything I have said...